Windows 7 Loader eXtreme Edition 3 uses retail MSDN keys, this is misleading as it combines them with certs in the UI, making it look like an OEM key.
When the keys reach their maximum activation limit or Microsoft blocks them, this will become useless, unless Napalum has an unlimited supply of MSDN keys.

Back up your tokens.dat file if you must have a version other than Ultimate.

This Loader uses the Ultimate tokens.dat file (the activation file corresponding to the RTM Ultimate key). That allows it to use the Ultimate Oem-Slp key (Dell/Lenovo) to activate other editions.

Note:
With the exception of Ultimate version, after using this tool, you may acquire a correct key for your edition and will not be able to change the key to your edition key without the correct tokens.dat file for your version.
If you backed up your original file you will have no problem.

Hopefully a newer build of this ‘Frankenbuild’ Loader will auto install a corresponding tokens.dat file that will later correspond to your edition key.